Is aftermarket down pipe alot louder than stock?

I'm thinking about replacing my stock down pipe( gutted top portion) with an aftermarket catted one. How much louder does it get for you guys when you make the swap?

Thanks

If you keep the stock mufflers, its nearly as quiet as stock.

^ +1. From outside the car no one will know if using OEM cans. From inside the car a slight amount of turbo noise is all you will hear.

Like whitetiger said, of true "exhaust noise" the increase is minimal in both absolute volume as well as harshness-of-tone. That part of the equation is controlled by the mufflers and the resonator (respectively).

 

But in terms of the turbo noise? like m sprank said, you'll hear a bit more of that, in-cabin. Most don't typically have a problem with that, though.

Thanks for the quick replies guys.

I'll echo that again. I'm running ERZ catless with stock catback, and it is marginally louder than stock, if at all.

I think you get a little louder with a larger intake, or by removing the stock intake silencer too...

Intake is WAY louder than DP, lol. I love the symphony of noise my SpecB makes. The wife hates it. Ah, the joys of having a car she won't drive.

^ +1.

 

An aftermarket SRI - particularly when paired with the factory BPV - will overwhelm the engine-sounds that an aftermarket DP will call-out from the turbo/wastegate and a "Stage II" tune.

 

It's like having Darth Vader underhood.

 

A panel filter - with or without pulling the intake silencer/resonator - bridges the quietness of having the factory airbox & resonator/silencer setup with the mouth-breather sounds of an aftermarket SRI + factory-BPV combo. For those who (or for whose passenger) wish a slightly quieter setup, albeit with some mechanical noises, that might be a decent compromise (note, however, that more recent observations by some of our own would suggest that Cobb's warning to not use their OTS mapping with even just a panel filter is a warning that you may want to consider, REF: http://legacygt.com/forums/showthread.php/intake-tuning-107711.html?t=107711).

Dude. I'm pretty sure my cobb sf airbox sent my motor internals into decay faster than they would have anyway... as the 08 2.5's had interal problems. messing with the intake on our cars is deadly if not tuned.

...messing with the intake on our cars is deadly if not tuned.

 

I think that's now more and more the thinking....

 

That even on an otherwise factory-stock BL/BP, such a change will push further out into the safety envelope. And given the unpredictable variability from one car to the other, it becomes a case of "no, it should not have, but yes, it actually did."

 

So, while I'm hesitant to say that it will always be problematic, I am definitely among those who will urge caution - to advise newcomers to our community to truly understand the implications of what such a change involves, and to make an adult decision based on that knowledge.

I tried a Purolator OEM replacement filter in full OEM airbox as a test. Installed it and went for a drive while logging.

 

Car ran lean in all cells. Within the range of adjustment of the ECU, but out of range of the tune. Made me feel uneasy enough to use only the brand filter (OEM) that the car was tuned with.

 

Cars are WAY touchy. Most owners just would not realize until too late.

I had always read "just drop in a K&N filter panel and be done with it"... I went the extra 9 and got the entire cobb airbox, which was certified by cobb and deemed worthy over the SPT box from Subaru.

 

Nice bump in tonal quality, some extra throttle response it seemed. I went on to do various other stage II stuff, an entire CBE, downpipe, etc.

 

Running lean is what made my internals go to hell much faster than they would have on their own.

 

The way I see it now, even though Subaru's ECU is pretty tolerant of changes, get even a simple, basic tune if you change anything but the silencer off the OEM intake. In fact, I would even say you can do the entire exhaust system over and be ok as long as the stock intake is on.

^Huh? Are you for real? Is this spam? Great first post.

he must work for car-stuff.com cause he has 2 posts both linking there.

 

It looks like spam to me.

I was commenting on his first post. He has since added another. Mods should shut down the user account.

 

Friggin spam.